If you move the global workspace out of the way before starting RStudio, does that help?

mv ~/.RData ~/.RData.backup

You might also try doing this with the RStudio Desktop session state folder:

mv ~/.rstudio-desktop ~/.rstudio-desktop-backup

Sorry if I'm misunderstanding -- are you able to do anything within the IDE after it's started up, or is it effectively frozen right from the start? If you monitor RAM usage by RStudio / the underlying rsession process, do you see it increasing in memory usage? You should be able to monitor its memory usage with one of the following: